fix

git-svn-id: http://svn.net-core.org/repos/t-engine4@4725 51575b47-30f0-44d4-a5cc-537603b46e54

@@ -2257,7 +2257,7 @@ function _M:unlearnTalent(t_id)
 	end
 
 	-- Unsustain ?
-	if not self:knowTalent(t_id) and t.mode == "sustained" then self:forceUseTalent(t_id, {ignore_energy=true}) end
+	if not self:knowTalent(t_id) and t.mode == "sustained" and self:isTalentActive(t_id) then self:forceUseTalent(t_id, {ignore_energy=true}) end
 
 	return true
 end